Vaccination

Vaccination protects women from becoming infected with vaccine-preventable infectious diseases. Vaccination is a much safer and less burdensome way to achieve disease immunity than infection.

The benefits of vaccination outweigh its risks. Vaccination involves injecting the body with either a pathogen that has been rendered harmless or killed or the pathogen particles. Either method makes a person’s immune system develop antibodies specific to the targeted pathogen, helping the body effectively fight diseases caused by the pathogen in the future. As a result, the actual transmission of the disease and the resulting risk of complications are eliminated. True, vaccination does not always prevent the onset of disease, but when it does, the disease vaccinated against is much milder and easier to treat than if a person has not been vaccinated. We recommended avoiding contact with children with viral illness during pregnancy, whether vaccinated or not. We also recommend going to bed early on the day before vaccination. If you are well-rested, you will produce significantly more antiviral antibodies following your vaccination.

Vaccination is essential during pregnancy because:

it protects mothers against infectious diseases that can be prevented by vaccination - cellular immunity is weakened during pregnancy, which can lead to, for example, severe flu;
by developing immunity, a pregnant mother also protects their unborn baby from infection;
for the first few months after being born, babies are protected by antibodies transferred from mother to fetus. By avoiding infection, a vaccinated mother protects the newborn. Vaccination, whether to protect against viruses or bacteria, is safe for pregnant mother and fetus alike.

It is recommended to vaccinate during pregnancy:

against the flu (influenza);
against whooping cough (pertussis);
against tick-borne encephalitis.

Vaccination of pregnant women against the flu

Pregnancy is demanding on a woman's body. During pregnancy, especially in the third trimester, a woman undergoes physiological changes, especially to their immune system, which loses some effectiveness. Due to changes in the cardiovascular and respiratory systems, pregnant women and women who have recently given birth are more at risk of serious complications from influenza. Although influenza is equally common in pregnant and non-pregnant women, the former is much more likely to develop pneumonia as a complication of influenza and need to be hospitalized more often. Pregnant women also have a higher mortality rate from pneumonia caused by influenza.

Influenza complications in pregnant women can include not only pneumonia, but also cardiovascular problems, miscarriage, premature and low birth weight, stillbirth, and birth defects. Although the influenza virus itself has not been shown to cause malformations, high fever in pregnant women may harm a fetus. Although the influenza vaccine does not prevent everyone from getting the disease, it does make the disease less severe.

A thimerosal-free influenza vaccine (Vaxigrip Tetra, Fluarix Tetra, or Influvac Tetra) is used to grant immunity to four strains of the influenza virus in the vaccine (two type A and two type B). Because vaccines do not contain infectious viruses, vaccination during pregnancy does not pose any additional risk to the fetus or mother, significantly increases a mother's resistance to the influenza virus. The safety of the flu vaccine during pregnancy and after birth (including for breastfeeding mothers and babies) has been scientifically proven. Vaccination provides necessary protection during pregnancy and the post-natal period when illness should be avoided as much as possible, as mothers and babies are both especially vulnerable during this time. Antibodies are also transferred from the vaccinated mother to their fetus, so their newborn is also protected against influenza. An influenza vaccine is only recommended for use in infants six months and older. Thus, a pregnant mother can grant passive immunity to their child (via antibodies passed down in the womb) for its first few months of life, when it is too young to be directly vaccinated.

Because the influenza virus can endanger a fetus, pregnant mothers should vaccinate against influenza with an inactivated influenza vaccine before the start of the flu season (the last weeks of September). Vaccination can also be done during flu season, but this is less ideal, as it takes an average of two weeks for immunity to develop. If a woman is exposed to the influenza virus before developing immunity via vaccine, their vaccination will not offer any protection, although the disease’s effects will not be any more severe than if the mother had not been vaccinated. A woman can be vaccinated against the flu in each trimester of pregnancy, and should especially be vaccinated in the second and third trimester. In Estonia, it is recommended to vaccinate against influenza in pregnant women whose second and third trimester take place during the height of flu season. As vaccination does not weaken the body, postponement of other vaccinations, such as against pertussis, is not needed.

Vaccination of a pregnant woman against pertussis

Pertussis, also known as “whooping cough,” is an acute respiratory disease characterized by weekly and even months-long periods of frequent and severe coughing attacks. Pertussis is particularly dangerous for infants, with the majority of deaths being related to infants under three months of age. Pertussis is one of the causes of sudden infant death. Complications of the disease include pneumonia, convulsive syndrome, and various extensive disorders of brain structure or function. At present, almost 10,000 children aged seven months to 14 years have not been vaccinated against pertussis in Estonia. As a result, the incidence of pertussis among young children has increased in recent years. As a child only receives the first dose of pertussis vaccine via the Estonian national vaccination program three months after birth, babies should be passively immunized against pertussis via the vaccination of their pregnant mother. Studies have shown that the greatest transmission of anti-pertussis antibodies through the placenta to the fetus occurs in the last four weeks of pregnancy. Therefore, it is recommended that pregnant women be vaccinated with diphtheria/tetanus/pertussis vaccine during the third trimester, during the 28-38 weeks of gestation.

Vaccination of pregnant women against tick-borne encephalitis

Tick-borne encephalitis is a viral disease of the central nervous system spread by ticks that can be severe and cause meningitis (inflammation of the meninges, the protective layer surrounding the brain and spine) or meningoencephalitis (inflammation of the brain and meninges). Most patients recover, but complications such as balance and coordination problems, limb paralysis, headaches, impaired concentration, and memory may persist. Tick-borne encephalitis is endemic to Estonia, so it is therefore recommended that all pregnant women in Estonia be vaccinated against the disease. Estonian ticks are active from April to September. In 2019, 83 people were infected with tick-borne encephalitis in Estonia. Only vaccination provides protection against tick-borne encephalitis. The tick-borne encephalitis vaccine contains an inactivated virus and is therefore safe for use in pregnant mothers. If the pregnant woman has not previously been vaccinated against tick-borne encephalitis, a complete vaccination against tick-borne encephalitis consisting of three injections should be performed. The first two are done one month apart and the third one a year after giving birth. After two injections, immunity has been established, but only for one season. The third injection prolongs immunity, which then only needs to be renewed every three to five years via a booster injection. An infant can be vaccinated against tick-borne encephalitis following their first birthday. Thus, a pregnant woman can grant her child passive immunity for its first year, until it can be vaccinated. A pregnant woman can be vaccinated against tick-borne encephalitis all year round, but the best time to do so is by March, before the high tick season.